1. Field of the Invention
The present invention relates to a management method of printed circuit boards in an assembling process of various types of electronic apparatuses having different arrangements of the printed circuit boards, and a management system for carrying out the method.
2. Description of the Related Art
Generally, an assembling process of electronic apparatuses having a plurality of printed circuit boards comprises assembling and testing steps of the printed circuit boards, and assembling and testing steps of the apparatuses on which the printed circuit boards have been mounted. In the case where various types of electronic apparatuses are assembled, the printed circuit boards produced in the former steps are stocked in a warehouse to synchronize with the latter steps.
Conventionally, the printed circuit boards which have been assembled and which have passed the test are put into a carrying box in such a manner that one carrying box contains the same type of printed circuit boards. The carrying box usually contains ten or twenty printed circuit boards of the same type. The carrying box containing the printed circuit boards is carried to the warehouse and the printed circuit boards are stocked in the carrying box on a shelf of the warehouse.
A printed circuit board which is used in the assembling steps of the apparatus is taken out of the warehouse while in the carrying box with other printed circuit boards of the same type, and is inserted into a given slot of a shelf of a rack for the apparatus.
In the aforementioned process, a sufficient amount of "goods in process", i.e. the finished printed circuit boards and racks, and sufficient retention time of the goods in process, is necessary for facilitating the assembling process. In addition, it is not easy to recognize whether all of the necessary printed circuit boards for assembling an apparatus are stocked in the warehouse, and much time and labor is required for gathering all of the necessary printed circuit boards. Namely, "board arrangement" is not easy.
In addition, it has been more important to identify the places where individual parts, especially large scale integrated circuits (LSI), mounted on the printed circuit boards, have been shipped to, in order to promptly take the necessary countermeasures against using formerly defective parts in the apparatus. To identify the location of the individual parts, it is necessary to record the types of the apparatus which are shipped and the production numbers or lot numbers of the individual parts mounted on the individual printed circuit boards used in the individual apparatuses. In the aforementioned process, however, recording this information is troublesome.